An issue was discovered in Django 6.0 before 6.0.6 and 5.2 before 5.2.15. `django.core.mail.backends.smtp.EmailBackend` in Django fails to prevent reuse of a partially-initialized connection after a failed `STARTTLS` handshake when `fail_silently=True`, which allows on-path network attackers to read email content via cleartext interception. Earlier, unsupported Django series (such as 5.0.x, 4.1.x, and 3.2.x) were not evaluated and may also be affected. Django would like to thank Kasper Dupont for reporting this issue.
History

Thu, 04 Jun 2026 00:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-325
References
Metrics threat_severity

None

threat_severity

Low


Wed, 03 Jun 2026 16:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 03 Jun 2026 15:45:00 +0000

Type Values Removed Values Added
First Time appeared Djangoproject
Djangoproject django
Vendors & Products Djangoproject
Djangoproject django

Wed, 03 Jun 2026 14:15:00 +0000

Type Values Removed Values Added
Description An issue was discovered in Django 6.0 before 6.0.6 and 5.2 before 5.2.15. `django.core.mail.backends.smtp.EmailBackend` in Django fails to prevent reuse of a partially-initialized connection after a failed `STARTTLS` handshake when `fail_silently=True`, which allows on-path network attackers to read email content via cleartext interception. Earlier, unsupported Django series (such as 5.0.x, 4.1.x, and 3.2.x) were not evaluated and may also be affected. Django would like to thank Kasper Dupont for reporting this issue.
Title Potential unencrypted email transmission via STARTTLS in the SMTP backend
Weaknesses CWE-319
References
Metrics cvssV3_1

{'score': 3.1, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N'}

cvssV4_0

{'score': 2.3, 'vector': 'CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: DSF

Published: 2026-06-03T13:16:15.446Z

Updated: 2026-06-03T15:43:34.012Z

Reserved: 2026-05-01T19:59:31.353Z

Link: CVE-2026-7666

cve-icon Vulnrichment

Updated: 2026-06-03T15:43:30.919Z

cve-icon NVD

Status : Received

Published: 2026-06-03T14:16:47.087

Modified: 2026-06-03T14:16:47.087

Link: CVE-2026-7666

cve-icon Redhat

Severity : Low

Publid Date: 2026-06-03T13:16:15Z

Links: CVE-2026-7666 - Bugzilla